Guidelines on application for Reassessment of Chemical Oxygen Demand
under the Sewage Services (Trade Effluent Surcharge) Regulation
Who can apply
1.A consumer liable to pay trade effluent surcharge (TES)but producestrade effluent of Chemical Oxygen Demand (COD) values lower than the generic values as stipulated in the Sewage Services (TES) Regulationcan apply for a variation of the TES rate.
How to apply
2.This can be done by having the COD valuesof the trade effluent,thus the TES rate,reassessed at his own expense by alaboratory accredited under the Hong Kong Laboratory Accreditation Scheme (HOKLAS laboratory)1in accordance with the “Technical Memorandum on procedures and methods for sampling and analysis of trade effluents” (“TM”)2, issued pursuant to section 13 of the Sewage Services Ordinance.
Procedure
3.This guideline explains the general procedures and requirements for the application for reassessment of COD values in the trade effluent. For detailed procedure of the reassessment, sampling, and testing, please refer to the TM.
3.1The applicant should appoint a HOKLAS laboratory (see Appendix I) to submit the application and sampling proposal3.
3.2In general, the application should include all information listed in Appendix II. A typical example of an application with sampling proposal, relevant information and forms to be submitted is given in Appendix IIIfor reference.
3.3Upon receipt of the application and sampling proposal, Drainage Services Department (DSD) will review and check the completeness of information submitted. If necessary, DSD will request the applicantto submit any missinginformation, further information, or clarification.
3.4When all the required information is received, DSD will inspect, if necessary, the site of the concerned premises normally within ten working days 4to confirm the sampling arrangement (Working Days define as Monday to Friday except public holidays).
3.5After the above inspection(if applicable)and the receipt of all the required information, a sampling schedule, taking into account the criteria set out in Appendix IV, will be mutually agreed between DSD and the HOKLAS laboratory/the applicant. DSD will then issue a notification of the confirmed sampling arrangement to the HOKLAS laboratory and the applicant.
3.6The HOKLAS laboratory should arrange the sampling to be conducted by competent samplers (see Appendix V), and testing for the trade effluent discharged from the premises concerned in accordance with the agreed sampling arrangement. The HOKLAS laboratory is required to split the sample collected, and submit one of the split samples to DSD for checking.
3.7When testing is completed, the HOKLAS laboratory shall submit a formal test report to DSD.
3.8If DSD considers that the COD reassessment results are adequately representative, the COD values will be approved and used to determine the new TES rate accordingly.
Points requiringspecial attention
4.Before submitting an application, the applicant is requested to pay attention to the following:-
4.1All water meter(s) must be functional (no sampling should take place unlessdysfunctional meter is properly repaired by the Water Supplies Department).
4.2All drainage outlets are free from blockage and functioning properly.
4.3Sampling tools are appropriate and in good condition.
4.4All water pipes (including the fire hose), water tanks (both fresh water and saline water), cooling tower(s) of air conditioning system etc. should be leakage free.
4.5All hydro-vent, if installed, must be operating normally and well maintained.
4.6All wastewater treatment facilities, including Central Grease Trap (CGT), if installed, are operating normally and free from overflow and blockage.
4.7The date and frequency of cleaning for the CGT as well as all pollution control measures such as the use of solid traps (strainers/spongy filters etc.) must be explicitly declared before commencing of the sampling and should be strictly adhered to at all times.
4.8Documentary evidence for use of chemical and/or biological treatment of the wastewater, if applicable, should be available upon request by DSD.
4.9Allequipment and machinery in the premises that may affect the quality of the effluentmust be operating normally. A suggested list of items to be checked for normal operation is given in Appendix VI for reference.
4.10DSD may inspect the site at any time during or after the sampling. The site inspection is to confirm that the agreed sampling methodology has been adopted during sampling, and thatthe trade activities and practices including all pollution control measures (such as dates and frequency of cleaning of CGT(s)) affecting the effluent quality are normal and strictly adhered to at all times.
4.11DSD may also collect sample(s) of trade effluent(s) discharged from the premises of the applicant concerned to verify the representativeness of the COD results submitted by the applicant.
4.12Resisting and delaying DSD’s staff in carrying out inspection and sampling without reason is deemed as acts of deception, and the COD reassessment application will be suspended by DSD.
4.13Any non-compliance will be deemed unacceptable. Once revealed, the sampling work of the day will be cancelled and test results of any sample collected will become void. DSD mayterminate the processing of anapplication if the non-compliance is serious. Practices that are considered asseriousnon-compliancesinclude but not limited to the following:
(i)Abnormal storage of wastewater;
(ii)Disposal and discharge of wastewater at point(s) other than that declared;
(iii)Disturbance of central grease trap(s) (scheduled periodic cleaning must not coincide with sampling period);
(iv)Water supply from sources (e.g. fire hose, water meter for toilet-flushing) other than the designated water meter(s);
(v)Kitchen activities that do not match the signed “Declaration of kitchen practice for restaurant and food factory (Form DSD/TES 3(e))”;
(vi)Some specific examples in which the applications are not accepted are given in Appendix VII.
Effective date and validity
5.If the approved COD values are lower than the generic values as shown in Appendix VIII, a new TES rate will be determined according to the charging matrix shown in Appendix IX and will take effect for three years.
6.The effective date of the new TES rate is determined as follows:
6.1For a new application, the effective date of the new TES rateshall be the first dayof the billing period within which the first date of sample collection falls and the COD values of suchsamples are accepted by DSD and used to determine the new TES rate.
6.2For a re-application, if the first day of the billing period mentioned in paragraph 6.1 falls immediately after or prior to the expiry of the lastapproved TES rate, the effective date of the new TES rate shall be thedate immediately after the expiry of the last approved TES rate; otherwise, it shall be the first day of the billing period within which the first date of sample collection falls and the COD values of suchsamples are accepted by DSD and used to determine the new TES rate.
7.Several hypothetical examples of approved application are shown in Appendix X.
Procedural flowchart
Maintenance of wastewater treatment,operation practices and measures, and recordkeeping during validity period
8.Throughout the validity period, the applicant shall maintain the wastewater treatment, operation practices and measuresas declared, and observe any other applicable conditions. DSD may also collect grab samples of the effluent discharged from the premises for the purpose of verifying the effluent strength against the approved COD values. All records showing that ongoing wastewater treatment, operation practices, and measuresare in line with those last declared must also be kept by the applicant on site for inspection. These records pertain, but are not limited, to those declared by the applicant under General Forms DSD/TES 3(e), DSD/TES 4(e), DSD/TES 5(e),DSD/TES 6(e)andDSD/TES 9(e). DSD will also request submission of these records by the applicant from time to time. In consideringa re-application, DSD may take into account any failure to maintain thedeclared wastewater treatment, operation practices and measures,or failure to submit such records upon request.
Notes
1 A list of HOKLAS accredited laboratories which have provided COD reassessment application service since 2005is attached in Appendix I for reference. To find other laboratories accredited for environmental testing, please refer tothe Directory of Accredited Tests and Calibrations at the Innovation and TechnologyCommissionwebsite:
(
2The TM can be downloaded at the DSD website: (
3In order to allow sufficient time for processing of a re-application, the consumer is advised to submit application at least one month before the expiry of the last revised TES rate should the applicant wish to have the new TES rate, if it is lower than the generic TES rate of the trade concerned, to be effective right after the expiry of the last revised TES rate.
4The time quoted may vary depending on the prevailing number of applications received by DSD.
Appendices
AppendixIList of HOKLAS laboratories which have provided COD reassessment application service since 2005
Appendix IIRelevant information to be submitted with the application of variation of Trade Effluent Surcharges (TES) rate
Appendix IIITypical example of sampling proposal and related information to be submitted with the application for COD reassessment
Appendix IVGuidance notes on arrangement of sampling
Appendix VCriteria for competent sampler
Appendix VISuggested list of items to be checked for normal operation
Appendix VIISome examples in which the application for COD reassessment will not be accepted
Appendix VIIITES chargeable trade, business or manufacture, their TES rates and generic COD values
Appendix IXTES rate matrices
Appendix XHypothetical examples of approved applications
General Forms
DSD/TES 1(e)Application Form for Reassessment of Chemical Oxygen Demand (COD) under the Trade Effluent Surcharge Scheme.
DSD/TES 2(e)Letter of Undertaking
DSD/TES 3(e)Declaration of kitchen practice for restaurant and food factory
DSD/TES 4(e)Declaration of proposed cleaning frequency and date(s) for Central Grease Trap(s)
DSD/TES 5(e)Declaration of use of sieves in drainage outlet(s) / surface channel(s)
DSD/TES 6(e)Declaration of use of sponge filters in drainage outlet(s) / surface channel(s)
DSD/TES 7(e)Declaration of giving up effective period of previously revised TES rate
DSD/TES 9(e) Grease Trap Waste Disposal Record
Enquires
Enquiries may be made to the DrainageServices Departmentat:-
G/FWestern Magistracy,
2APok Fu LamRoad,
Hong Kong
Tel. : 2834 9432
Fax : 2574 5645